1. Field of the Invention
The present invention relates to the technology field of heat sinks, and more particularly to a novel microchannel structure and a heat sink having the same.
2. Description of the Prior Art
With the semiconductor technologies being highly developed, the application of semiconductor laser devices, such as laser scalpel, laser soldering equipment, and laser pointer, being getting broader with the increase of their output power. Because the electro-optical conversion efficiency of the semiconductor laser device is about 30%˜50%, there has about 50%˜70% of electric energy being converting to heat under the operation of the semiconductor laser device; therefore, it is able to image that the performance and reliability of the semiconductor laser device would be largely reduced due to the heat accumulation excessively produced in the semiconductor laser device.
Accordingly, microchannel heat sink has proposed by Tuckerman and Pease in 1981, and is widely applied to various semiconductor laser devices for the heat dissipation purpose. Please refer to FIG. 1, which illustrates a framework view of a conventional semiconductor laser apparatus. As shown in FIG. 1, a plurality of semiconductor laser units 100′ are stacked to form the conventional semiconductor laser apparatus 200′, wherein each of the semiconductor laser units 100′ consists of a semiconductor laser device array 2′ and a heat sink 10′ corresponding to the semiconductor laser device array 2′. Moreover, a cooling device 510′ is connected to the heat sink 10′ by a piping 600′ for transmitting a refrigerant fluid into the heat sink 10′ through the operation of a circulation pump 520′, so as to enhance the heat-dissipating ability of the heat sink 10′.
Continuously referring to FIG. 1, and please simultaneously refer to FIG. 2, there is shown an exploded view of the heat sink 10′. As shown by FIG. 2, the heat sink 10′ consists of: an inlet layer 20′, a communication layer 30′, and an outlet layer 40′, wherein the inlet layer 20′ is provided with a first opening 22′ and a second opening 24′ thereon. In addition, a first flow groove 26′ with bell-shaped appearance is further formed on the inlet layer 20′ and connected with the first opening 22′.
Inheriting to above descriptions, the communication layer 30′ is provided with a third opening 32′ opposite to the first opening 22′ and a fourth opening 34′ opposite to the second opening 24′ thereon. Moreover, multiple micro fluid-guiding channels 36′ are disposed on the communication layer 30′. On the other hand, the outlet layer 40′ is provided with a fifth opening 42′ opposite to the third opening 32′ and a sixth opening 44′ opposite to the fourth opening 34′. In addition, a second flow groove 46′ with bell-shaped appearance is further formed on the outlet layer 40′ and connected with the sixth opening 44′. In the heat sink 10′, the first opening 22′, the third opening 32′ and the fifth opening 42′ form an inlet port 160′ for receiving the refrigerant fluid transmitted from the piping 600′. Opposite to the inlet port 160′, the second opening 24′, the fourth opening 34′ and the sixth opening 44′ form an outlet port 180′ for transmitting the refrigerant fluid to the piping 600′.
Moreover, in the heat sink 10′, because the diameter of the micro fluid-guiding channels 36′ of the communication layer 30′ is designed to about 1 μm˜1000 μm, the refrigerant fluid would be accelerated to a jet current when the refrigerant fluid in the first flow groove 26′ flows into the second flow groove 46′ via the micro fluid-guiding channel 36′, so as to enhance the heat dissipating ability of the heat sink 10′. However, despite that the heat sink 10′ of FIG. 2 performs high heat dissipating ability, the inventors of the present invention find that the heat sink 10′ still includes many drawbacks after practically applying the heat sink 10′:
(1) Although the design of the micro fluid-guiding channels 36′ facilitate the flow speed of the refrigerant fluid and the heat dissipating ability of the heat be largely enhanced, the power of the circulation pump 520′ is simultaneously increased due to the high pressure difference inducted between two ends of the micro fluid-guiding channels 36′.
(2) Please refer to FIG. 3, which illustrates a cross-sectional view of the heat sink 10′, wherein the section plane of the heat sink 10′ shown in FIG. 3 is obtained by cutting the diagram of the heat sink 10′ shown in FIG. 2 along the cutting plane line A′-A′. As shown in FIG. 3, since both the fluid-guiding corner 261′ formed between the first flow groove 26′ and the first channel opening 361′ of the micro fluid-guiding channels 36′ as well as the fluid-guiding corner 461′ formed between the second flow groove 46′ and the second channel opening 362′ of the micro fluid-guiding channels 36′ are a 90° corner, such 90° fluid-guiding corner would form a hindrance for causing the refrigerant fluid in the first flow groove 26′ be unable to effectively flow into the micro fluid-guiding channels 36′. Moreover, after the heat sink 10′ is used for a long term, it can find that the two 90° fluid-guiding corners are damaged by the high-speed scouring corrosion of the refrigerant fluid.
Accordingly, in view of the conventional micro fluid-guiding channels 36′ and the heat sink 10′ reveal many practically-used drawbacks, the inventor of the present application has made great efforts to make inventive research thereon and eventually provided a novel microchannel structure and a heat sink having the novel microchannel structure.